System and method of automatic detection of obstructions for a robotic catheter system

ABSTRACT

An obstruction detection system for a robotic catheter system including a robotic catheter manipulator assembly including one or more catheter manipulation bases and one or more sheath manipulation bases. Each manipulation base may be generally linearly movable on one or more tracks relative to the robotic catheter manipulator assembly. The obstruction detection system may include one or more obstruction detection sensors disposed on the track or on the manipulation bases to detect an obstruction along a path of motion of one or more manipulation bases. A software system may be provided for monitoring movement of the catheter and sheath manipulation bases, and/or a status of the obstruction detection sensors.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a national stage tiling based upon internationalapplication no. PCT/US2009/058121, filed 23 Sep. 2009 and published inEnglish on 1 Apr. 2010 under international publication no. WO2010/036746 (the '121 application), which claims priority to and is acontinuation-in-part of U.S. non-provisional application Nos.12/347,811, filed 31 Dec. 2008 now U.S. Pat. No. 8,343,096 (the '811application), Ser. No. 12/347,826, filed 31 Dec. 2008 now U.S. Pat. No.8,317,744 (the '826 application), Ser No. 12/347,835, filed 31 Dec. 2008now U.S. Pat. No. 8,684,962 (the '835 application), Ser. No. 12/347,842,filed 31 Dec. 2008 now U.S. Pat. No. 8,317,745 (the '842 application),each of which claim the benefit of U.S. provisional application No.61/099,904, filed 24 Sep. 2008 (the '904 application). The '811application, the '826 application, the '835 application, the '842application, and, subsequently, this application also claim the benefitof U.S. provisional application No. 61/040,143, filed 27 Mar. 2008 (the'143 application). The '121, '811, '826, '835, '842, '143, and '904applications are hereby incorporated by reference as though fully setforth herein.

BACKGROUND OF THE INVENTION

a. Field of the Invention

This invention relates to a robotic catheter system and method forautomated control of a catheter and related components. In particular,the instant invention relates to a robotic catheter system including asystem and method for detection of obstructions that may hinder orotherwise stop movement of catheter and/or sheath manipulation bases,and related components during operation of the robotic catheter system.

b. Background Art

Electrophysiology catheters are used in a variety of diagnostic and/ortherapeutic medical procedures to correct conditions such as atrialarrhythmia, including for example, ectopic atrial tachycardia, atrialfibrillation, and atrial flutter. Arrhythmia can create a variety ofdangerous conditions including irregular heart rates, loss ofsynchronous atrioventricular contractions and stasis of blood flow whichcan lead to a variety of ailments and even death.

Typically in a procedure, a catheter is manipulated through a patient'svasculature to, for example, a patient's heart, and carries one or moreelectrodes which may be used for mapping, ablation, diagnosis, or othertreatments. Once at the intended site, treatment may include radiofrequency (RF) ablation, cryoablation, lasers, chemicals, high-intensityfocused ultrasound, etc. An ablation catheter imparts such ablativeenergy to cardiac tissue to create a lesion in the cardiac tissue. Thislesion disrupts undesirable electrical pathways and thereby limits orprevents stray electrical signals that lead to arrhythmias. As readilyapparent, such treatment requires precise control of the catheter duringmanipulation to and at the treatment site, which can invariably be afunction of a user's skill level.

One method of minimizing invariability due to a user's skill levelinvolves the use of robotic catheter systems, such as the roboticcatheter system described in detail in commonly owned and copendingapplication Ser. No. 12/347,811 titled “Robotic Catheter System”. Asreadily evident, such robotic catheter systems include a variety ofsafety concerns that must be addressed to prevent harm to a patient andthe system operator. One such safety concern includes the possibility ofan obstruction in the path of manipulation bases supporting the catheterand sheath cartridges, the layout and operation of which is alsodescribed in detail in the aforementioned “Robotic Catheter System”application.

The inventors herein have thus recognized the need for a system andmethod for detection of obstructions that may hinder or otherwise stopmovement of manipulation bases and related components, and have furtherrecognized the need for a system and method for controlling movement ofthe manipulation bases in a predetermined manner based on the type andlocation of an obstruction, and other factors involving movement of themanipulation bases.

BRIEF SUMMARY OF THE INVENTION

An obstruction detection system for a robotic catheter system mayinclude a robotic catheter manipulator assembly including one or morecatheter and sheath manipulation bases, with each manipulation basebeing generally linearly movable on one or more tracks relative to therobotic catheter manipulator assembly. The obstruction detection systemmay include one or more obstruction detection sensors disposed on thetrack and/or on the manipulation bases to detect an obstruction along apath of motion of the manipulation bases.

For the obstruction detection system described above, in one embodiment,the obstruction detection sensors may be ultrasonic sensors orlight-emitting sensors. In one embodiment, the obstruction detectionsystem may include obstruction detection sensors located at both ends ofthe track. In another embodiment, the obstruction detection system mayinclude obstruction detection sensors located at both longitudinal endsof the catheter and sheath manipulation bases. In one embodiment of theobstruction detection system, the obstruction detection sensors enablemaintenance of a predetermined distance between the catheter and sheathmanipulation bases.

For the obstruction detection system described above, in one embodiment,the system may include a software system for monitoring movement of thecatheter and sheath manipulation bases, and/or a sensor status of one ormore obstruction detection sensors. In one embodiment of the obstructiondetection system, the software system may include code for determiningif a relative distance between the catheter and sheath manipulationbases is less than a predetermined distance; if the relative distance isless than the predetermined distance, then indicating an obstructionstatus of the catheter and sheath manipulation bases as obstructed, andstopping motion of the catheter and sheath manipulation bases, and ifthe relative distance is greater than or equal to the predetermineddistance, then indicating the obstruction status of the catheter andsheath manipulation bases as unobstructed, and allowing motion of thecatheter and sheath manipulation bases. In another embodiment, theobstruction detection system may include LEDs, visual signals, audiblesignals, and/or haptic feedback to a user input device, for indicatingthe obstruction status of the catheter and sheath manipulation bases.

For the obstruction detection system described above, in one embodiment,the system may include code for determining a relative distance betweenthe catheter and sheath manipulation bases by determining an amount ofrotation of motors that drive the catheter and sheath manipulationbases. In one embodiment of the obstruction detection system, thesoftware system may include code for stopping motion of the catheter andsheath manipulation bases if the sensor status of the obstructiondetection sensors is obstructed, and allowing motion of the catheter andsheath manipulation bases if the sensor status of all obstructiondetection sensors is unobstructed.

For the obstruction detection system described above, in one embodiment,the system may include code for determining a direction of travel of thecatheter and sheath manipulation bases, and allowing motion of thecatheter and sheath manipulation bases if the sensor status of one ofthe obstruction detection sensors is obstructed, only if the directionof travel is away from the obstruction. In one embodiment of theobstruction detection system, the software system may include code fordetermining a direction of travel of the catheter and sheathmanipulation bases by determining a direction of rotation of motors thatdrive the catheter and sheath manipulation bases.

For the obstruction detection system described above, in one embodiment,the system may include LEDs, visual signals, audible signals, and/orhaptic feedback to a user input device, for indicating the sensor statusof the obstruction detection sensor. In one embodiment of theobstruction detection system, the software system may monitor themanipulation bases and the obstruction detection sensors by means of aCANOpen protocol standard.

The invention also provides an obstruction detection system for arobotic catheter system including a robotic catheter manipulatorassembly including one or more catheter manipulation bases and one ormore sheath manipulation bases, with each manipulation base beinggenerally linearly movable on one or more tracks relative to the roboticcatheter manipulator assembly. The obstruction detection system mayinclude detection means disposed on the track or on the manipulationbases to detect an obstruction along a path of motion of themanipulation bases, and monitoring means for monitoring movement of thecatheter and sheath manipulation bases, and/or a detection status of thedetection means.

For the obstruction detection system described above, in one embodiment,the detection means may be an ultrasonic sensor or a light-emittingsensor. In one embodiment of the obstruction detection system, thedetection means may include obstruction detection sensors located atboth ends of the track. In another embodiment of the obstructiondetection system, the detection means may include obstruction detectionsensors located at both longitudinal ends of the catheter and sheathmanipulation bases. In one embodiment of the obstruction detectionsystem, the obstruction detection sensors may enable maintenance of apredetermined distance between the catheter and sheath manipulationbases.

For the obstruction detection system described above, in one embodiment,the system may include monitoring means in the form of a software systemincluding code for determining if a relative distance between thecatheter and sheath manipulation bases is less than a predetermineddistance; if the relative distance is less than the predetermineddistance, then indicating an obstruction status of the catheter andsheath manipulation bases as obstructed, and stopping motion of thecatheter and sheath manipulation bases, and if the relative distance isgreater than or equal to the predetermined distance, then indicating theobstruction status of the catheter and sheath manipulation bases asunobstructed, and allowing motion of the catheter and sheathmanipulation bases.

For the obstruction detection system described above, in one embodiment,the system may include means for indicating the obstruction status ofthe catheter and sheath manipulation bases. In one embodiment of theobstruction detection system, the means for indicating may include LEDs,visual signals, audible signals, and/or haptic feedback to a user inputdevice.

For the obstruction detection system described above, in one embodiment,the system may include monitoring means in the form of a software systemincluding code for determining a relative distance between the catheterand sheath manipulation bases by determining an amount of rotation ofmotors that drive the catheter and sheath manipulation bases.

For the obstruction detection system described above, in one embodiment,the system may include monitoring means in the form of a software systemincluding code for stopping motion of the catheter and sheathmanipulation bases if the detection status of the obstruction detectionsensors is obstructed, and allowing motion of the catheter and sheathmanipulation bases if the detection status of all obstruction detectionsensors is unobstructed. In one embodiment of the obstruction detectionsystem, the monitoring means may be a software system including code fordetermining a direction of travel of the catheter and sheathmanipulation bases, and allowing motion of the catheter and sheathmanipulation bases if the detection status of one of the obstructiondetection sensors is obstructed, only if the direction of travel is awayfrom the obstruction. In one embodiment of the obstruction detectionsystem, the monitoring means may be a software system including code fordetermining a direction of travel of the catheter and sheathmanipulation bases by determining a direction of rotation of motors thatdrive the catheter and sheath manipulation bases.

For the obstruction detection system described above, in one embodiment,the system may include means for indicating the detection status of theobstruction detection sensor. In one embodiment of the obstructiondetection system, the means for indicating may include LEDs, visualsignals, audible signals, and/or haptic feedback to a user input device.In one embodiment of the obstruction detection system, the monitoringmeans may monitor the manipulation bases and the detection means bymeans of a CANOpen protocol standard.

The foregoing and other aspects, features, details, utilities andadvantages of the present invention will be apparent from reading thefollowing description and claims, and from reviewing the accompanyingdrawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an isometric diagrammatic view of a robotic catheter system,illustrating an exemplary layout of various system components;

FIG. 2 is an enlarged isometric view of an exemplary robotic cathetermanipulator assembly, also shown in FIG. 1;

FIGS. 3a-3c are enlarged isometric views of an embodiment of a roboticcatheter manipulator assembly, and FIGS. 3d-3g are respectively enlargedleft side, right side, top and front views of the robotic cathetermanipulator assembly of FIG. 3a , illustrating use of the manipulatorassembly with a robotic catheter rotatable device cartridge;

FIGS. 4a-4c are enlarged isometric views of an embodiment of amanipulation base;

FIGS. 5a-5e are enlarged isometric views of an embodiment of a roboticcatheter device cartridge, with FIG. 3a illustrating an exemplary usageof the robotic catheter device cartridge;

FIG. 6 is a sketch illustrative of exemplary placement of obstructiondetection sensors for the obstruction detection system according to theinvention; and

FIG. 7 is a flow-chart of the control logic for the obstructiondetection system according the invention.

DETAILED DESCRIPTION OF EMBODIMENTS OF THE INVENTION

Referring now to the drawings wherein like reference numerals are usedto identify identical components in the various views, an embodiment ofrobotic catheter system 10 (described in detail in commonly owned andcopending application Ser. No. 12/347,811 titled “Robotic CatheterSystem”), also referred to as “the system,” may be likened to “fly bywire” operation for a catheter system. The system may be used, forexample, to manipulate the location and orientation of catheters andsheaths in a heart chamber or in another body cavity. As shown in FIG.1, robotic catheter system 10 may generally incorporate a human inputdevice and control system (referred to as “input control system”) 100,e.g., a joystick and related controls (described briefly below and indetail in commonly owned and copending Application Serial No.PCT/US2009/038618 titled “Robotic Catheter System Input Device”), that auser such as an electrophysiologist (EP) may interact with, anelectronic control system 200 (described briefly below and in detail incommonly owned and copending Application Serial No. PCT/US2009/038597titled “Robotic Catheter System with Dynamic Response”) that translatesmotions of the user at the input device into a resulting movement of acatheter tip, and a visualization system 12 that provides a user withreal-time or near-real-time positioning information concerning thecatheter tip. The system may further include closed-loop feedback usingan EnSite NavX™ Navigation and Visualization system 14 and/or opticalforce transducers, a robotic catheter manipulator assembly 300(described briefly below and in detail in commonly owned and copendingapplication Ser. No. 12/347,826 titled “Robotic Catheter ManipulatorAssembly”) for operating a robotic catheter device cartridge 400(described briefly below and in detail in commonly owned and copendingapplication Ser. No. 12/347,835 titled “Robotic Catheter DeviceCartridge” and application Ser. No. 12/347,842 “Robotic CatheterRotatable Device Cartridge”), and manipulator support structure 500(described briefly below and in detail in commonly owned and copendingapplication Ser. No. 12/347,811 titled “Robotic Catheter System”). Asdiscussed in detail below, robotic catheter system 10 may include anobstruction detection system 600 for detection of obstructions that mayhinder or otherwise stop movement of catheter and sheath manipulationbases, and related components during operation of the robotic cathetersystem. The respective disclosures of the above-identified and othercommonly owned and copending applications discussed in this applicationare incorporated herein by reference.

Before proceeding with a detailed description of obstruction detectionsystem 600, the general layout and operation of the components ofrobotic catheter system 10 will be described with reference to FIGS. 1-5e to provide a basis for the operation of obstruction detection system600.

An embodiment of robotic catheter system 10 may involve automatedcatheter movement. A user, such as an EP, could identify locations(potentially forming a path) on a rendered computer model of the cardiacanatomy. The system can be configured to relate those digitally selectedpoints to positions within a patient's actual/physical anatomy, and maycommand and control the movement of a catheter to defined positions.Once in position, either the user or system could then perform thedesired treatment or therapy—which may further be in accordance with adefined algorithm. This system could enable full robotic control byusing optimized path planning routines together with closed-loopposition control. Furthermore, the system could automate certain“best-practices,” such as pulling the catheter across the surface, ormaking contact at an oblique angle.

Referring to FIG. 1, input control system 100, described below and incommonly owned and copending application titled “Robotic Catheter SystemInput Device,” may generally allow a user to control the movement andadvancement of both the catheter and sheath. Generally, several types ofjoysticks may be employed, including, without limitation, instrumentedtraditional catheter handle controls, oversized catheter models,instrumented, user-wearable gloves, and traditional joysticks. Inembodiments, for example and without limitation, the joystick may bespring or motor centering so that any movement from the center positioncauses an incremental movement of the actual catheter tip, or thejoystick may work in absolute terms.

Referring to FIG. 1, electronic control system 200 will be describedbriefly.

As discussed in detail in commonly owned and copending applicationstitled “Robotic Catheter System Input Device,” and “Robotic CatheterSystem with Dynamic Response,” many additional features may be includedwith embodiments of the system to, for example, improve the accuracy oreffectiveness of the system. Such features may include, closed-loopfeedback using EnSite NavX™ Navigation and Visualization system 14 forcreating realistic cardiac chamber geometries or models, displayingactivation timing and voltage data to identify arrhythmias, and guidingprecise catheter movement, and/or optical force transducers; activetensioning of “passive” steering wires to reduce the system responsetime; cumulative ablation while the tip is following a front-to-backironing motion; and/or reactive/resistive impedance monitoring.

Referring to FIG. 1, visualization system 12 will be described briefly.

Visualization system 12 may provide a user with real-time ornear-real-time positioning information concerning the catheter tip. Inan exemplary embodiment, system 12 may include an EnSite NavX™Navigation and Visualization monitor 16 for displaying cardiac chambergeometries or models, displaying activation timing and voltage data toidentify arrhythmias, and for facilitating guidance of cathetermovement. A fluoroscopy monitor 18 may be provided for displaying areal-time x-ray image or for assisting a physician with cathetermovement. Additional exemplary displays may include an ICE and EP Prukadisplays, 20, 22, respectively.

Referring to FIG. 1, EnSite NavX™ Navigation and Visualization system 14will be described briefly.

EnSite NavX™ Navigation and Visualization system 14 (described in detailin U.S. Pat. No. 7,263,397, titled “Method and Apparatus for CatheterNavigation and Location and Mapping in the Heart,” incorporated byreference in its entirety) may be provided for creating realisticcardiac chamber geometries or models, displaying activation timing andvoltage data to identify arrhythmias, and guiding precise cathetermovement. System 14 may collect electrical data from catheters and usethis information to track or navigate their movement and constructthree-dimensional (3-D) models of the chamber.

Referring to FIGS. 1-5 e, robotic catheter manipulator assembly 300 foroperating robotic catheter device cartridges 400, various embodiments ofwhich are described in detail in the aforementioned commonly owned andcopending applications, will be described briefly for facilitating anunderstanding of input control system 100, and the operationalintegration of an haptic feedback system 900 with manipulator assembly300 for controlling cartridges 400.

As generally shown in FIGS. 1 and 3 a-5 e, robotic catheter system 10which includes one or more robotic catheter manipulator assemblies 300,includes an embodiment of robotic catheter manipulator assembly 302including both catheter and sheath manipulation mechanisms 304, 306 formanipulating, for example, catheter and sheath cartridges 402, 404.Manipulator assembly 302 may include interconnected/interlockingmanipulation bases 308, 310 for catheter and sheath cartridges 402, 404,and likewise may include electrical “handshake” functionality asdiscussed below. Each interlocking base 308, 310 may be capable oftravel in the longitudinal direction of the catheter/sheath (D₁, D₂respectively). In an embodiment, D₁ and D₂ may each represent atranslation of approximately 8 linear inches. As shown in FIG. 3a , eachinterlocking base may be translated by high precision drive mechanisms312, 314. Such drive mechanisms may include, for example and withoutlimitation, a motor driven lead screw or ball screw.

As shown in FIGS. 3a-5e , for each cartridge 402, 404, an associatedmanipulation base 308, 310 may include a plurality of fingers 316, 318,320 and 322, (e.g., one per steering wire) that extend or protrudeupwardly to contact and interact with the steering wire slider blocks(such as slider blocks 412, 414, 416, 418) to independently tensionselect steering wires 420, 422, 424, 426. Each finger can be configuredto be independently actuated by a precision drive mechanism, such as amotor driven ball screw 324, and may be outfitted with force sensors tomeasure corresponding steering wire tension. A distal steering wireencoder (not shown) may also be provided for force measurements at thedistal end of the steering wires adjacent the catheter distal end. Eachmotor driven ball screw (for both finger control and cartridgetranslation control) may further include encoders to measure a relativeand/or an absolute position of each element of the system. As shown inFIG. 4a , bearing 332 and coupler 330 of ball screw 324 may engage frame340 of respective bases 308, 310 and a corresponding finger 316, 318,320 or 322 may be mounted adjacent a strain gauge for measuring thecorresponding steering wire tension.

Referring to FIGS. 4a-4c , bases 308, 310 may include exemplarycomponents such as motors 342, 344, 346 and 348, respectively coupled tofingers 316, 318, 320 and 322. A bearing 354 may be provided for slidingof bases 308, 310 on track 356. A plurality of inductive sensors (e.g.home sensors) 358 may be provided for guiding each manipulation base toa safe position.

Referring to FIGS. 1-3 g, particularly FIGS. 3d-3g , robotic cathetermanipulator assembly 302 may be usable with a robotic catheter rotatabledevice cartridge 490, described in detail in commonly owned andcopending application titled “Robotic Catheter Rotatable DeviceCartridge.” As shown in FIG. 3g , manipulator base 308 may be replacedwith a robotic catheter rotatable drive head 492 and a robotic catheterrotatable drive mechanism 494, described in detail in commonly owned andcopending application titled “Robotic Catheter Rotatable DriveMechanism.”

Referring to FIGS. 1 and 5 a-5 e, an embodiment of catheter and sheathcartridges 402, 404 will be described in detail.

As briefly discussed above, robotic catheter system 10 may include oneor more cartridges 400, with manipulator 302 including at least twocartridges 402, 404, each of which may be respectively designed tocontrol the distal movement of either the catheter or the sheath. Withrespect to catheter cartridge 402, catheter 406 may be substantiallyconnected or affixed to cartridge 402, so that advancement of cartridge402 correspondingly advances catheter 406, and retraction of thecartridge retracts the catheter. As further shown in FIGS. 5a-5e anddiscussed above, in an embodiment, each cartridge 402, 404 may includeslider blocks (e.g., 412, 414, 416, 418), each rigidly (andindependently) connected or affixed to one of a plurality of cathetersteering wires (e.g., 420, 422, 424, 426) in a manner that permitsindependent tensioning of each steering wire. The cartridge may beprovided as a disposable item that is capable of being easily positioned(e.g., snapped) into place in an overall assembly. In an embodiment, asdiscussed in detail below, the cartridge may include an electrical“handshake” device or component to allow the system to properly identifythe cartridge (e.g., by type and/or proper placement/positioning).Sheath cartridge 404 may be designed in a similar manner as the cathetercartridge 402, but will typically be configured to provide for thepassage of catheter 406. Assembly 302 may include a plurality (e.g., asmany as ten or more) of independent driving mechanisms (e.g. motordriven ball screws 324).

For some embodiments, the catheter and sheath cartridge can be designedto be substantially similar, and in that context a reference to eithermay relate to both. For example, as shown in FIGS. 5a-5e , the design ofthe catheter/sheath cartridge may include upper and lower cartridgesections 428, 430, and independent slider blocks 412, 414, 416, 418. Thesystem is not generally limited to specific material selection orformation techniques. However, in an embodiment, the upper and lowercartridge sections 428, 430 may be injection molded using apolycarbonate material. Each slider block 412, 414, 416, 418 may beconnected to a separate catheter steering wire 420, 422, 424, 426, andmay be formed of a Teflon-like material such as, for example, Delrin AF.When in contact with the cartridge housing portions 428, 430, suchTeflon-like slider blocks may maintain a low static and dynamiccoefficient of friction and may avoid the need for additionallubrication.

Referring to FIGS. 3a-5e and as discussed above, catheter and sheathcartridges 402, 404 may be configured to secure or lock down ontorespective interconnecting catheter and sheath manipulation bases 308,310. To couple cartridge 402 (and 404) with base 308 (and 310), one ormore locking pins (e.g., 432 in FIGS. 5a, 5d and 5e ) on the cartridgemay engage one or more mating recesses 360 in the base (see FIG. 4a ).In an embodiment, such recesses 360 may include an interference locksuch as a spring detent or other locking means. In an embodiment, suchother locking means may include a physical interference that may requireaffirmative/positive action by the user to release the cartridge. Suchaction may include or require actuation of a release lever 362.Additionally, as shown in FIGS. 5c, 5d and 5e , cartridge 402 (and 404)may include one or more locator pins 434 that are configured topassively fit into mating holes on the base (e.g., 364 in FIG. 4a ).

In an embodiment, a user (e.g. an EP) may first manually positioncatheter 406 and sheath 410 (with catheter 406 inserted in sheath 410)within the vasculature of a patient. Once the devices are roughlypositioned in relation to the heart, the user may then engage or connect(e.g., “snap-in”) the catheter cartridge into place oninterconnecting/interlocking bases 308, 310 of manipulator assembly 302,for example, by inserting the locking/locating pins 432, 434 of thecartridges into mating holes 360, 364 of respective base 308, 310. Whenthe cartridge is interconnected with the base, each of the plurality offingers 316, 318, 320 or 322 may fit into recesses formed between thedistal edge of slider blocks 412, 414, 416, 418 and a lower portion ofthe cartridge housing. Such recesses are shown in, for example, FIGS. 5d and 5 e. With sufficiently rigid coupling between each slider blockand a corresponding steering wire, pushing a slider block in a proximaldirection may cause an attached steering wire to tension and thuslaterally deflect the distal end of the catheter and sheath 406, 410.

The aforementioned electrical handshake between manipulation bases 308,310 and catheter and sheath cartridges 402, 404 will be describedbriefly.

Robotic catheter system 10 may be useful for a variety of procedures andin connection with a variety of tools and/or catheters. Such toolsand/or catheters may include, without limitation, spiral catheters,ablation catheters, mapping catheters, balloon catheters, needle/dilatortools, cutting tools, cauterizing tools, and/or gripping tools. Thesystem may additionally include a means of identifying the nature and/ortype of catheter/tool cartridge that is installed for use, and/orposition or connection related information. The system may automaticallyaccess/obtain additional information about the cartridge, such as,without limitation, its creation date, serial number, sterilizationdate, prior uses, etc.

Further, some embodiments of the system may include an ability to “read”or detect the type or nature of the connected cartridge through the useof memory included with the disposable cartridge together with somedata/signal transmission means. By way of example, each cartridge maycontain a chip (e.g., an EEPROM chip) that can be electricallyinterfaced by the manipulator head. Such a chip could, for instance, beprogrammed during the manufacturing process and may electronically storevarious data, such as the make; model; serial number; creation date;and/or other special features associated with the cartridge or tool.Additionally the chip may contain other worthwhile information, such asan indication of previous use, catheter specific calibration data,and/or any other information that may relate to the safety orperformance of the particular device.

In an embodiment, upon interconnecting the cartridge (e.g. 402, 404)with the manipulator head (e.g. 302), a detection means, such as anoptical or magnetic sensor, may initially detect the presence of thecartridge. Once presence is detected, the manipulator may energize achip and initiate data/signal retrieval. Such retrieved data/signal maythen be used by the system to control or alter various features and/ordisplays based on the type of device and/or information provided. Whileone embodiment may use a chip (e.g., EEPROM), due to its designflexibility, another embodiment may include a wireless transmissiondevice, such as an RFID, which may be employed to facilitate the datastorage/transfer instead of, or in addition to a chip.

Referring now to FIGS. 1-7, and particularly FIGS. 6 and 7, obstructiondetection system 600 of the invention will be described in detail, andmay generally include a hardware system 700 and a software system 800.

Referring to FIG. 6, hardware system 700 may include a plurality ofobstruction detection sensors 702, 704, 706, 708, 710 and 712 (describedin detail below) generally operatively interconnected with softwaresystem 800 for enabling, disabling or otherwise controlling movement ofmanipulation bases 308, 310. Obstruction detection system 600 mayinitiate control, or otherwise disable movement of manipulation bases308, 310 as the bases generally move towards or away from each other ontrack 356 based on the particular nature of the operation beingperformed by a physician during surgery or by a technician, for example,during maintenance, or by a physician or technician during attachment ordetachment of cartridges 402, 404. Since manipulator assembly 302generally includes an enclosure 370 as shown in FIG. 2 partially orfully covering manipulation bases 308, 310, during typical operation,the general working area of manipulation bases 308, 310 remains covered.However, in the event of an obstruction being present in the path ofmanipulation bases 308, 310 or during routine maintenance of manipulatorassembly 302 where a technician or operator may insert an object orfinger in the area of manipulation bases 308, 310, enclosure 370 may beremoved for access to manipulation bases 308, 310. The combination ofhardware system 700 and a software system 800, as discussed herein, maydetect the presence of an obstruction in the path of manipulation bases308, 310 and stop movement of bases 308, 310 when certain criteria havebeen met.

In further detail, as shown in FIGS. 3a and 6, hardware system 700 maygenerally include obstruction detection sensors 702, 704, 706, 708, 710and 712 respectively disposed on or along track 356 and manipulationbases 308, 310. In a particular embodiment of the invention, sensors702-712 may be ultrasonic sensors, or alternatively, light-emittingsensors for detecting the presence of an obstruction. Sensors 702 and712 may be disposed at the opposing ends of track 356, and sensors 704,706, and 708, 710 may be respectively disposed at the corners or othersuitable locations on manipulation bases 310, 308. Sensors 702, 704 maymonitor the presence of any obstructions along Path 1 betweenmanipulation base 310 and end 714 of track 356. Sensors 706, 708 maymonitor the presence of any obstructions along Path 2 betweenmanipulation bases 310 and 308, and sensors 710, 712 may monitor thepresence of any obstructions along Path 3 between manipulation base 308and end 716 of track 356. As discussed below, any positive (e.g. towardend 714) and negative (e.g. toward end 716) translation of manipulationbase 308, 310 would be stopped in case of an obstruction along track356.

Referring to FIG. 7, software system 800 operates in combination withhardware system 700 to track motion of manipulation bases 308, 310 ontrack 356, and more specifically, whether the manipulation bases aremoving in a positive or negative direction, and their distance from eachother. Typically, manipulation bases 308, 310 are designed to movewithin 2-3 millimeters of each other to prevent collision. Softwaresystem 800 may selectively activate one or more of sensors 702-712 uponactuation or movement of manipulation bases 308, 310 in a predetermineddirection to detect any obstructions in the path of translation of aspecific manipulation base. Alternatively, all sensors 702-712 may beactivated so that software system 800 determines a proper course ofaction based on the location of an obstruction (e.g. along Path 1, Path2 or Path 3), and other factors such as the direction of movement of themanipulation bases, and the actual function being performed (e.g.surgery or routine maintenance). Based on the specific function beingperformed, software system 800 may stop movement of the manipulationbases (e.g. by cutting power to high precision drive mechanisms 312,314), allow movement of the manipulation bases, or reverse movement ofthe manipulation bases.

For example, if an obstruction is present along Path 2 and routinemaintenance is being performed on manipulator assembly 302, softwaresystem 800 may stop movement of manipulation bases 308, 310 if they aremoving toward each other, but can allow movement of the manipulationbases if they are moving away from each other. In this manner, if anobstruction (e.g. a hand or finger of a service technician) is presentalong Path 2, movement of the manipulation bases may only be halted ifthe bases are moving towards each other (e.g. to prevent contact with anobstruction), but may be otherwise allowed to continue. If theobstructions is present along Path 2, in a routine maintenance mode,manipulation bases 308, 310 may be directed to move away from each othersuch that a predetermined distance (e.g. 20 mm) remains between thebases for insertion of a technician's fingers or another object alongPath 2 for maintenance operations.

One method of detecting motion of manipulation bases 308, 310 may be todetect the direction of motion of high precision drive mechanisms 312,314, which operate via the CANOpen protocol standard. Referring to FIG.7, the algorithm for software system 800 is illustrated and may includea motion command request at location 802 for initiating or continuingmotion of manipulation bases 308, 310. At location 804, software system800 may determine if high precision drive mechanisms 312, 314 aremoving, and if not, motion may be initiated at location 806. At location808, if high precision drive mechanisms 312, 314 are moving at step 804or motion is initiated at step 806, then system 800 may determine if theposition of the sheath manipulation base 310 minus the position of thecatheter manipulation base 308 is less than a predetermined obstructionposition delta (e.g. a predetermined safe distance between the sheathand catheter drive mechanisms; 20 mm in the example discussed above).Alternatively, at location 808, the system may also determine if any ofthe obstruction detection sensors 702-712 have been activated. If thedetermination at location 808 is no, then motion may continue atlocation 810. If the determination at location 808 is yes, then atlocation 812, system 800 may set an Obstruction Status flag toObstructed, and turn LED 718 to red, as discussed in detail below withreference to FIG. 2. Thereafter at location 814, high precision drivemechanisms 312, 314 may be stopped by turning the power off or by othermeans. The off status of high precision drive mechanisms 312, 314 maythen be fed to CANOpen protocol 816 for further evaluation. Once theObstruction Status flag is cleared (e.g. no obstruction), LED 718 may beturned to green, as also discussed below.

The LED will be turned off as soon as the obstruction status flag iscleared.

In a particular embodiment, software system 800 may monitor highprecision drive mechanisms 312, 314, for example, every 50 ms todetermine the direction of movement and location of manipulation bases308, 310 (e.g. location along track 356, and relative location).Software system 800 may thus monitor manipulation bases 308, 310, whichoperate via the CANOpen protocol standard, and further monitor thepresence of any obstruction along Paths 1-3 as detected by sensors702-712. Upon the detection of an obstruction, software system 800 mayissue instructions through the CANOpen protocol to stop high precisiondrive mechanisms 312, 314, and thus manipulation bases 308, 310.

Thus, referring again to FIG. 7, at location 816, CANOpen protocol mayreceive input from locations 810, 820 and 822, which are respectively,monitors for sheath high precision drive mechanism 314, catheter highprecision drive mechanism 312, and obstruction sensors 702-712. The datafrom the respective locations 810, 820 and 822 may be sampled at apredetermined rate (e.g. 50 ms) and fed into location 804 to determinemovement of the catheter/sheath high precision drive mechanisms, andfurther evaluation as discussed above.

The combination of hardware system 700 including obstruction detectionsensors 702-712, and software system 800 which monitors sensors 702-712and high precision drive mechanisms 312, 314 operable via the CANOpenprotocol standard, provides for an obstruction detection system 600 thatmonitors for obstructions along Paths 1-3 and stops motion ofmanipulation bases 308, 310 depending on factors such as the position ofan obstruction, the direction of travel of the manipulation bases, andthe type of operation being performed (e.g. surgery, routinemaintenance, or cartridge replacement). Yet further, depending on theextent and location of an obstruction, system 600 may cut off power toall high precision drive mechanisms (e.g. 312, 314, 342, 344, 346 and348; see FIGS. 3a and 4b ), or just selective drive mechanisms dependingon whether the obstruction is detected during surgery or maintenance.During surgery, this selective disablement of certain high precisiondrive mechanisms would allow critical functions to be performed, withoutentire system shut-down.

Referring to FIG. 2, a LED 718 may be provided for conveying theoperational status of robotic catheter system 10 to a user. In aparticular embodiment, LED 718 may include, for example, three lightcolor indicators such as red, yellow, green for respectively indicatingthe requirement for system shutdown, a problem and the requirement forsystem maintenance, or proper system operation. Alternatively, LED 718may include codes via, for example, blinks to indicate the type ofproblem. An emergency on/off switch 720 may also be provided to manuallyshut robotic catheter system 10 off in the event of an emergency, and asa redundant measure for shutting down system 10 and motion ofmanipulation bases 308, 310.

With the addition of obstruction detection system 600 to roboticcatheter system 10, set-point calibration can be fully automated withthe presence of obstruction detection sensors 702-712. Set-pointcalibration assures that when catheter and sheath cartridges 402, 404are in place, there is a minimum amount of tension on steering wires420, 422, 424 and 426 to enable control of the catheter/sheath. Forexample, in order to automate movement of catheter and sheath 406, 410,and set-point calibration during system initialization, system 600 mayprevent movement of manipulation bases 308, 310 if an obstruction isdetected along Paths 1-3. Specifically, once catheter and sheathcartridges 402, 404 are snapped onto manipulation bases 308, 310, if anobstruction is detected along Paths 1-3 by obstruction detection sensors702-712, set-point calibration would not initiate until the user clearsthe obstruction. Such functionality would enhance the EP experience byproviding additional safety for the robotic catheter system, and wouldalso provide safety to a patient so that the desired movement of thesheath and catheter can be achieved without any obstruction.Additionally, obstruction detection system 600 may be include othervisible or audible signals, and/or be integrated with haptic feedbacksystem 900 so that when an obstruction is detected, haptic feedback isprovided to a user via input control system 100 to stop further motionof the manipulation bases 308, 310, as well as catheter and sheathcartridges 402, 404, as needed.

The invention thus provides an obstruction detection system 600 fordetection of obstructions that may hinder or otherwise stop movement ofmanipulation bases 308, 310, and related components. As discussed above,hardware system 700 and software system 800 of obstruction detectionsystem 600 may operate in a cohesive manner to control movement of themanipulation bases in a predetermined manner based on the type andlocation of an obstruction, and other factors involving direction ofmovement of the manipulation bases.

Although several embodiments of this invention have been described abovewith a certain degree of particularity, those skilled in the art couldmake numerous alterations to the disclosed embodiments without departingfrom the scope of this invention. All directional references (e.g.,upper, lower, upward, downward, left, right, leftward, rightward, top,bottom, above, below, vertical, horizontal, clockwise andcounterclockwise) are only used for identification purposes to aid thereader's understanding of the present invention, and do not createlimitations, particularly as to the position, orientation, or use of theinvention. Joinder references (e.g., attached, coupled, connected, andthe like) are to be construed broadly and may include intermediatemembers between a connection of elements and relative movement betweenelements. As such, joinder references do not necessarily infer that twoelements are directly connected and in fixed relation to each other. Itis intended that all matter contained in the above description or shownin the accompanying drawings shall be interpreted as illustrative onlyand not as limiting. Changes in detail or structure may be made withoutdeparting from the invention as defined in the appended claims.

What is claimed is:
 1. An obstruction detection system for a roboticcatheter system including a robotic catheter manipulator assemblyincluding at least one catheter manipulation base and at least onesheath manipulation base, each manipulation base being generallylinearly movable on at least one track relative to the robotic cathetermanipulator assembly, the obstruction detection system comprising: atleast one obstruction detection sensor disposed on the track or on atleast one of the manipulation bases to detect an obstruction along apath of motion of at least one of the manipulation bases; and anelectronic control system configured to control movement of the at leastone catheter manipulation base and the at least one sheath manipulationbase and to receive a signal indicating an obstruction along the path ofmotion; wherein the at least one obstruction detection sensor isconfigured to send the signal indicating an obstruction along the pathof motion to the electronic control system.
 2. The obstruction detectionsystem according to claim 1, wherein the obstruction detection sensor isan ultrasonic sensor or a light-emitting sensor.
 3. The obstructiondetection system according to claim 1, further comprising obstructiondetection sensors located at both ends of the track.
 4. The obstructiondetection system according to claim 1, further comprising obstructiondetection sensors located at both longitudinal ends of the catheter andsheath manipulation bases.
 5. The obstruction detection system accordingto claim 4, wherein the obstruction detection sensors enable theelectronic control system to maintain a predetermined distance betweenthe catheter and sheath manipulation bases.
 6. The obstruction detectionsystem according to claim 1, wherein the electronic control systemcomprises software that includes code for: determining if a relativedistance between the catheter and sheath manipulation bases is less thana predetermined distance, if the relative distance is less than thepredetermined distance, then indicating an obstruction status of thecatheter and sheath manipulation bases as obstructed, and stoppingmotion of the catheter and sheath manipulation bases, if the relativedistance is greater than or equal to the predetermined distance, thenindicating the obstruction status of the catheter and sheathmanipulation bases as unobstructed, and allowing motion of the catheterand sheath manipulation bases.
 7. The obstruction detection systemaccording to claim 6, further comprising at least one of a LED, a visualsignal, an audible signal, and haptic feedback to a user input device,for indicating the obstruction status of the catheter and sheathmanipulation bases.
 8. The obstruction detection system according toclaim 1, wherein the electronic control system comprises software thatincludes code for: determining a relative distance between the catheterand sheath manipulation bases by determining an amount of rotation ofmotors that drive the catheter and sheath manipulation bases.
 9. Theobstruction detection system according to claim 1, wherein theelectronic control system comprises software that includes code for:stopping motion of the catheter and sheath manipulation bases if thesensor status of at least one of the obstruction detection sensors isobstructed; and allowing motion of the catheter and sheath manipulationbases if the sensor status of all obstruction detection sensors isunobstructed.
 10. The obstruction detection system according to claim 9,further comprising at least one of a LED, a visual signal, an audiblesignal, and haptic feedback to a user input device, for indicating thesensor status of the obstruction detection sensor.
 11. The obstructiondetection system according to claim 1, wherein the electronic controlsystem comprises software that includes code for: determining adirection of travel of the catheter and sheath manipulation bases; andallowing motion of the catheter and sheath manipulation bases if thesensor status of one of the obstruction detection sensors is obstructed,only if the direction of travel is away from the obstruction.
 12. Theobstruction detection system according to claim 1, wherein theelectronic control system comprises software that includes code for:determining a direction of travel of the catheter and sheathmanipulation bases by determining a direction of rotation of motors thatdrive at least one of the catheter and sheath manipulation bases. 13.The obstruction detection system according to claim 1, wherein theelectronic control system comprises software that monitors themanipulation bases and the obstruction detection sensors by means of aCANOpen protocol standard.
 14. The obstruction detection systemaccording to claim 1, wherein the electronic control system isconfigured to cut power to the at least one catheter manipulation baseand the at least one sheath manipulation base before the obstructiondetection sensor contacts an obstruction.
 15. An obstruction detectionsystem for a robotic catheter system including a robotic cathetermanipulator assembly including at least one catheter manipulation baseand at least one sheath manipulation base, each manipulation base beinggenerally linearly movable on at least one track relative to the roboticcatheter manipulator assembly, the obstruction detection systemcomprising: detection means disposed on the track or on at least one ofthe manipulation bases to detect an obstruction along a path of motionof at least one of the manipulation bases; and monitoring meanscomprising a software system for monitoring at least one of movement ofthe catheter and sheath manipulation bases, and a detection status ofthe detection means, wherein the software system is configured to movethe at least one catheter manipulation base and the at least one sheathmanipulation base on the at least one track; and wherein the detectionmeans is configured to send a signal indicating an obstruction along thepath of motion to the software system.
 16. The obstruction detectionsystem according to claim 15, wherein the detection means is anultrasonic sensor or a light-emitting sensor.
 17. The obstructiondetection system according to claim 15, wherein the detection meansincludes obstruction detection sensors located at both ends of thetrack.
 18. The obstruction detection system according to claim 15,wherein the detection means includes obstruction detection sensorslocated at both longitudinal ends of the catheter and sheathmanipulation bases.
 19. The obstruction detection system according toclaim 18, wherein the obstruction detection sensors enable the softwaresystem to maintain a predetermined distance between the catheter andsheath manipulation bases.
 20. The obstruction detection systemaccording to claim 15, wherein the software system comprises code for:determining if a relative distance between the catheter and sheathmanipulation bases is less than a predetermined distance, if therelative distance is less than the predetermined distance, thenindicating an obstruction status of the catheter and sheath manipulationbases as obstructed, and stopping motion of the catheter and sheathmanipulation bases, if the relative distance is greater than or equal tothe predetermined distance, then indicating the obstruction status ofthe catheter and sheath manipulation bases as unobstructed, and allowingmotion of the catheter and sheath manipulation bases.
 21. Theobstruction detection system according to claim 20, further comprisingmeans for indicating the obstruction status of the catheter and sheathmanipulation bases.
 22. The obstruction detection system according toclaim 20, wherein the means for indicating is at least one of a LED, avisual signal, an audible signal, and haptic feedback to a user inputdevice.
 23. The obstruction detection system according to claim 15,wherein the software system comprises code for: determining a relativedistance between the catheter and sheath manipulation bases bydetermining an amount of rotation of motors that drive the catheter andsheath manipulation bases.
 24. The obstruction detection systemaccording to claim 15, wherein the software system comprises code for:stopping motion of the catheter and sheath manipulation bases if thedetection status of at least one of the obstruction detection sensors isobstructed; and allowing motion of the catheter and sheath manipulationbases if the detection status of all obstruction detection sensors isunobstructed.
 25. The obstruction detection system according to claim24, further comprising means for indicating the detection status of theobstruction detection sensor.
 26. The obstruction detection systemaccording to claim 25, wherein the means for indicating is at least oneof a LED, a visual signal, an audible signal, and haptic feedback to auser input device.
 27. The obstruction detection system according toclaim 15, wherein the software system comprises code for: determining adirection of travel of the catheter and sheath manipulation bases; andallowing motion of the catheter and sheath manipulation bases if thedetection status of one of the obstruction detection sensors isobstructed, only if the direction of travel is away from theobstruction.
 28. The obstruction detection system according to claim 15,wherein the software system comprises code for: determining a directionof travel of the catheter and sheath manipulation bases by determining adirection of rotation of motors that drive at least one of the catheterand sheath manipulation bases.
 29. The obstruction detection systemaccording to claim 15, wherein the monitoring means monitors themanipulation bases and the detection means by means of a CANOpenprotocol standard.